Activation of Endogenous Retroviruses in Dnmt1−/− ESCs Involves Disruption of SETDB1-Mediated Repression by NP95 Binding to Hemimethylated DNA Acute loss of the maintenance methyltransferase Dnmt1 induced widespread DNA demethylation and transcriptional activation of endogenous retroviruses, including CpG-rich intracisternal A particle proviruses. Researchers showed that this effect is not due simply to a loss of DNA methylation. Conditional deletions revealed that both Dnmt1 and Np95 are essential for maintenance DNA methylation. [Cell Stem Cell] Abstract | Graphical Abstract Dynamic and Flexible H3K9me3 Bridging via HP1β Dimerization Establishes a Plastic State of Condensed Chromatin The authors defined a fundamental mechanism for chromatin higher order structural changes caused by heterochromatin protein 1 (HP1) proteins, which might contribute to the plastic nature of condensed chromatin. [Nat Commun] Full Article Melatonin Improves Reprogramming Efficiency and Proliferation of Bovine-Induced Pluripotent Stem Cells Researchers studied how primary cultured bovine neural stem cells (NSC) isolated from the retinal neural layer could transform into NSC-derived pluripotent stem cells cell. [J Pineal Res] Abstract Small Molecules Facilitate Single Factor-Mediated Hepatic Reprogramming Investigators report that direct conversion into induced hepatocyte-like cells is a stepwise transition involving the erasure of somatic memory, mesenchymal-to-epithelial transition, and induction of hepatic cell fate in a sequential manner. [Cell Rep] Full Article | Graphical Abstract Distinct Signaling Requirements for the Establishment of ESC Pluripotency in Late-Stage EpiSCs Investigators showed that chemical inhibition of casein kinase 1alpha induces the conversion of recalcitrant late-stage epiblast stem cell (EpiSC) into embryonic stem cell (ESC) pluripotency. [Cell Rep] Full Article | Graphical Abstract MicroRNAs of the miR-290–295 Family Maintain Bivalency in Mouse Embryonic Stem Cells Examining the contribution of microRNAs (miRNAs) to the regulation of bivalent genes, researchers found that the miRNA biogenesis enzyme DICER was required for the binding of the PRC2 core components EZH2 and SUZ12, and for the presence of the PRC2-mediated histone modification H3K27me3 at many bivalent genes. [Stem Cell Rep] Full Article Nucleosome Positioning Changes during Human Embryonic Stem Cell Differentiation To better understand nucleosome positioning, scientists used MNase-seq to investigate changes that occur as human embryonic stem cells transition to nascent mesoderm and then to smooth muscle cells. [Epigenetics] Abstract Improved Survival and Initiation of Differentiation of Human Induced Pluripotent Stem Cells to Hepatocyte-Like Cells upon Culture in William’s E Medium followed by Hepatocyte Differentiation Inducer Treatment Although human induced pluripotent stem cells initiate hepatocyte differentiation, most die within 7 days. In this study, the authors investigated both hepatocyte differentiation inducer and conventional media for their potential to improve cell survival. [PLoS One] Full Article Inhibition of Lysine-Specific Demethylase-1 (LSD1/KDM1A) Promotes the Adipogenic Differentiation of hESCs Through H3K4 Methylation The authors investigated the functional role of LSD1 during the adipogenic differentiation of human embryonic stem cells (hESCs) involving the demethylation of H3K4. They also found that treating hESCs with the LSD1 inhibitor CBB1007 promotes the adipogenic differentiation of hESCs. [Stem Cell Rev] Full Article |